People who eat asparagus may notice in the minutes and hours after consuming the green vegetable that their urine develops a strange, and usually undesirable, pungent smell. This phenomenon is a mystery to some people who either never detect the odor change or never produce it themselves. In fact, studies have shown that only approximately 50% of the population will experience the post-asparagus consumption odor change.http://www.healthdiaries.com/eatthis/asparagus-and-urine-odor-what-causes-it.html According to studies only 33% of people are able to detect the smell even when present.http://www.mensfitness.com/nutrition/354

So what is the cause of the stink? Science isn't certain of the answer. Of the numerous theories that have been generated, the most scientifically accepted theory is this: There is an amino acid in asparagus called methionine that breaks down into the compound methylmercaptan (aka mercaptan) in the urine during digestion. This compound contains sulfur (from the same family of sulfurs that makes the skunk smell), which may contribute to the stink. The compound may only appear in the urine of people who have the gene that enables them to break down mercaptan.http://www.asparagus.org/maab/faq.html

Scientists have found that the smell change is superficial and is harmless.http://www.healthdiaries.com/eatthis/asparagus-and-urine-odor-what-causes-it.html There is, unfortunately, no known way to eliminate the smell, aside from avoiding eating asparagus.

The topic of asparagus and its tie to urine odor has been noted through history and was immortalized in the book Swann's Way by Marcel Proust, where the following quote comes from:

"...the precious essence that I recognized again when, all night long following a dinner at which i had eaten them, they played, in farces as crude and poetic as a fairy play by Shakespeare, at changing my chamber pot into a jar of perfume."http://www.healthdiaries.com/eatthis/asparagus-and-urine-odor-what-causes-it.html

The content in this page is not a substitute for professional medical advice. Please contact a doctor before using the information presented here.